Unitary hammer spring and trigger spring for firearms



June 10, 1952 D. M. WILLIAMS UNITARY HAMMER-SPRING AND TRIGGER-SPRINGFOR FIREARMS Filed Dec. 13, 1949 b A Z H 5/ Patented June 10, 1952 UNITE UNITARY HAMMER SPRING AND TRIGGER SPRING FOR FIREARMS corporation ofDelaware Application December 13, 1949, Serial No. 132,657

7 Claims. 1

The present invention relates in general to firearms and more especiallyto improved firecontrol means of economical and simplified construction.

An object of the invention is to provide the fire-control means of afirearm with a single unitary element to serve both as a hammer-springand as a trigger-spring.

A further object of the invention is to provide the fire-control meansof a firearm with a unitary hammer-spring and trigger-spring foreffecting low cost of manufacture and economy of space and smooth anduniform operation.

A further object of the invention is to provide the fire-control meansof a firearm with a unitary hammer-spring and trigger-spring wherein thehammer-spring constitutes a helical spring which is used for pivotallymounting the hammer in the frame of the firearm while a reach of thehelical spring serves as the trigger-spring.

A still further object of the invention is to provide the fire-controlmeans of a firearm with a unitary resilient element of durable anddependable construction to serve as a hammerspring, as a pivotal supportfor the hammer, as a trigger-spring, and as means for locking thetrigger pivot-pin and the trigger-plate and frameassembly pin in thetrigger-plate of the firearm.

Other objects and advantages will appear to those skilled in the artfrom the following, considered in conjunction with the accompanyingdrawings.

In the accompanying drawings, in which certain modes of carrying out thepresent invention are shown for illustrative purposes:

Fig. 1 is a side elevation of the trigger-plate of a firearm embodyingthe improved unitary hammer-spring and trigger-spring of this invention,the hammer being shown by full lines in its cocked position and bybroken lines in its firing position;

Fig. 2 is a rear end elevation of the triggerplate shown in Fig. l withthe hammer in its cocked position;

Fig. 3 is a plan elevation partly in section of the trigger-plate ofFigs. 1 and 2 showing the hammer mounted on the unitary hammer-springand trigger-spring of this invention;

Fig. 4 is an enlarged end elevation in section on line 4-4 of Fig. 1showing the trigger-plate and frame-assembly pin of the trigger-platelocked therein by the reach of the unitary hammer-spring andtrigger-spring;

Fig. 5 is an enlarged elevation in section on a 2 line 5-5 of Fig. 1showing the pivot-pin of the trigger locked in the trigger-plate by thereach of the unitary hammer-spring and triggerpr Fig. 6 is an enlargedperspective view of the unitary hammer-spring and trigger-spring of thisinvention;

Fig. '7 is an enlarged perspective view of the assembly-pin forassembling the trigger-plate in the frame of the firearm;

Fig. 8 is an enlarged perspective view of the trigger pivot-pin; and

Fig. 9 is an enlarged perspective view of the hammer of the fire-controlmeans.

For the purpose of illustrating the present invention, the latter isembodied in a firearm of the type wherein the fire-control mechanism isassembled as a unit in a trigger-plate which constitutes a separableframe-member of the frame of the firearm and which is adapted to bedetachably secured thereto by means of an assembly-pin in the mannerhereinafter described. It will be understood, however, that theinvention is applicable to firearms of the type wherein the firecontrolmechanism is assembled directly in the frame of the firearm and that theillustrated embodiment of the invention is not a limitation thereof, thescope of which is defined by the appended claims.

General construction Referring to the drawings, the trigger-plate onwhich the unitary hammer-spring and triggerspring of this invention isassembled is indicated generally at H] and comprises asubstantiallyrectangular body-portion having two longitudinalspaced-parallel substantially-vertical side walls I I and [2respectively, the left-hand side wall 1 I (as seen in Fig. 2) beingconsiderably thicker than the right-hand side wall l2. The longitudinalslot l3 which extends between the two side walls H and I2 is adapted toaccommodate a hammer l4 and a trigger 15, the latter including a sear l6which, in the normal forward position of the trigger, is adapted toengage the cocking-lip ll of the hammer to hold it in its cockedposition as shown in Fig. 1, and to disengage the cocking-lip I! of thehammer when the triggerfinger I8 is pulled rearwardly to discharge thefirearm. The scar I6 is located on the trigger l5 forwardly of thepivot-pin IQ of the trigger, the forward extremity 20 of the triggerbeing-adapted to be held upwardly normally in position for cooperativeengagement with a cam-lug 2| of the hammer-hub 22 by means ofatrigger-spring tion.

The aforesaid trigger-plate i is assembled in the frame 23 (Fig. 4) ofthe firearm by engaging a pair of trigger-plate tongues 24, which extendforwardly from the front end of the trig ger-plate, in correspondingrecesses of the frame; and by inserting an assembly-pin 25 throughaxially-aligned apertures 26 and 21 in the rear ends of thetrigger-plate and frame respectively.

Unitary hammer-spring and trigger-spring The improved unitaryhammer-spring and trigger-spring of this invention is indicatedgenerally by the numeral 28, and embodies a hammer-spring which servesas means for pivotally mounting the hammer in the trigger-plate; and atrigger-spring for resiliently holding the trigger in its normal forwardposition. The hammerspring per se comprises a helical spring 29 havingat one end a relatively-short finger 30, and at its opposite end arelatively-long resilient reach 3|. The latter is bent substantiallyintermediate its opposite ends to provide a knee 32, the free end of theresilient reach being bent bacle on itself to form a substantiallyU-shaped hook 33, the short leg 34 of which is bent downwardly withrespect to the resilient reach so as to engage the rear end of thetrigger as shown in Fig. 1. The short leg 34 of the resilient reach thusserves as a trigger-spring by engagement with the upper surface of therear end-portion 35 of the trigger, the short leg or trigger-spring 34being of concave curvature to provide a satisfactory bearing against theupper surface of the trigger.

The helical convolutions of the hammer-spring 29 are adapted to functionas a bushing for pivotally mounting the hammer in the longitudinal slotl3 of the trigger-plate and to this end, the hammer-hub 22 is providedwith a cylindrical aperture 36 extending transversely therethrough, thediameter of the cylindrical aperture 36 corresponding substantially tothe maximum outside diameter of the helical hammer-spring 29, wherebythe latter may be assembled therein. As shown especially well in Fig. 3,the over-all length of the hammer-spring 29 exceeds the width of thehammer-hub 22 by an amount corresponding substantially to the thicknessof the left-hand side wall ll of the trigger-plate. To mount the hammerand hammer-spring in the slot I3 of the trigger-plate, the side wall I Iof the trigger-plate is provided with a cylindrical aperture 31extending transversely therethrough and corresponding in diameter to themaximum outside diameter of the hammer-spring 29, theoutwardly-extending portion of the hammer-spring 29 being adapted toengage in the aperture 31 and to be supported by the circumferentialwalls thereof.

The opposite or inner end of the hammerspring 29 engages in the aperture36 of the hammer-hub and forms a supporting-bushing therefor, the innerend of the hammer-spring being normally freely mounted on a pin 38having a substantially-cylindrical shank-portion 39 which extendsthrough the hammer-spring. A stopcollar 40 is provided on the pin 38adjacent one end thereof, but spaced inwardly therefrom a distancecorresponding substantially to the thickness of the corresponding sidewall I 2 of the trigger-plate so as to form a pin-pilot 4|. The latteris adapted to be mounted in an aperture 42 in the aforesaid side wall l2of the triggerplate to support the corresponding end of the pin therein,with its stop-collar 40 abutting the inner surface of the side wall 12to prevent the pin from moving through the aperture 42 thereof, theaperture 42 being in axial alignment with the spring-supporting aperture37 in the lefthand side wall H of the trigger-plate. As assembled thusin the trigger plate, the inner end of the hammer-spring 29 will abutagainst the stop-collar 40, the diameter of which is slightly less thanthe diameter of the aperture 36 in the hammer.

To function as a hammer-spring for actuating the hammer of the firearm,the reach 3| of the helical spring 29 is adapted to be anchored to thetrigger-plate, the opposite end of the helical spring 29 beingdetachably secured to the hammer. To this end, the rear wall of thehubaperture 36 is provided with a longitudinal groove 44 in which thefinger 30 of the hammer-spring is adapted to engage, thereby to securethe heli cal hammer-spring against rotation in the aperture of the hub.As shown especially well in Fig. 3, access to the longitudinal groove inthe aperture of the hammer-hub is provided by forming a similar groove45 in the rear wall of the springsupporting aperture 31 in the side wallll of the trigger-plate, the two grooves 44 and 45 being in axialalignment when the hammer is in its cocked position. In this connection,it will be apparent that when the hammer is cooked, the spring 29 istensioned, with the result that the convolutions of the helical springare contracted such that the outside and inside dimensions of thehelical spring are slightly less than the corresponding dimensions whenthe hammer is in its normal firing position, at which time the aforesaiddimensions are substantially maximum.

As pointed out above, when the helical spring is in its normal firingposition, its inner end is supported freely on the pin 38. However, whenthe hammer is cocked, the resulting decrease in the inside diameter ofthe helical sprin is such that the latter makes a close fit around thepin so as to insure engagement of the hammer-lip with the sear.

In order to anchor the resilient reach 3| of the hammer-spring to thetrigger-plate and, in particular, substantially flush with the outerface of the left-hand side wall H thereof, the aforesaid face isprovided with a clearance-recess 46 which extends from the forward wallof the hammerspringsupporting-aperture 31 in the side wall II of thetrigger-plate rearwardly to intersect the rear end of the side wall, theupper edge or shoulder 4! of the clearance-recess adjacent the rear endof the side wall I I being undercut as at 48, as indicated especiallywell in Fig. 5, to accommodate the corresponding end of theresilientreach 3|, thereby to prevent the rear end thereof fromspringingoutwardly of the clearance-recess. The bottom edge or shoulder49 of the clearance-recess adjacent the pivot-pin I9 of the trigger issubstantially coincident with the axis of the pivot-pin, as aconsequence of which the upper half of the corresponding end of thetrigger pivot-pin I9 is exposed, this exposed portion of the pivot-pinbeing immediately rearward of'the knee 32 of the resilient reach. Asshown especially well in Figs. 5 and 8, this exposed end of thepivot-pin I9 is provided with an annular groove 50, the depth of whichcorresponds substantially to one-half the diameter of the resilientreach 3|. The latter, and in particular the portion thereof immediatelyrearwardly of its knee 32, is adapted thus to snap into an adjacentportion of the groove 58, and by engagement with the transverse wallsthereof to lock the pivot-pin 19 in its assembled position in thetrigger-plate. In a similar manner, the trigger-plate assemblypin 25 isprovided with an annular groove 5| in the end thereof which projectsfrom the lefthand side wall H of the trigger-plate. As illustratedespecially well in Fig. 4, the grooved end of the assembly-pinintersects the undercut-portion 48 of the upper shoulder 41 of thetriggerplate, whereby the corresponding portion of the resilient reach3| is adapted to snap into the groove 5| of the assembly-pin 25 to lockthe latter to the trigger-plate. As assembled thus in theclearance-recess 4-3 of the trigger-plate, the U-shaped hook-portion 33of the resilient reach 3| encircles the rear end of the left-hand sidewall H of the trigger-plate so as to enter the trigger-spring as intothe rear end of the slot I3 of the trigger-plate for engagement with therear end 35 of the trigger.

From the foregoing description and drawings, it will be clear that, asassembled in the triggerplate of the firearm, the unitary hammer-springand trigger-spring constitutes a hammer-spring for actuation of thehammer and serves also as a bushing for pivotally mounting the hammer inthe trigger-plate. Moreover, the resilient reach of the hammer-springserves as a trigger-spring to resiliently hold the trigger in its normalinoperative position, and also as means for locking the triggerpivot-pin and the trigger-plate assembly-pin in position in thetrigger-plate. The unitary hammer-spring and trigger-spring is thus asingle element which is of durable and economical construction, whichoccupies a minimum of space in the trigger-plate, and which performs amultiplicity of functions essential to the operation of the fire-controlmechanism.

The invention may be carried out in other specific ways than thoseherein set forth without departing from the spirit and essentialcharacteristics of the invention, and the present embodiments are,therefore, to be considered in all respects as illustrative and notrestrictive, and all changes coming within the meaning and equivalencyrange of the appended claims are intended to be embraced therein.

I claim:

1. A unitary hammer-spring spring for a firearm embodying aframe-member, a hammer having an apertured hub, a sear, and a triggerhaving an operative connection with said sear for holding said sear incooking engagement with said hammer, said unitary hammerspring andtrigger-spring comprising: a helical spring constructed and arranged tobe supported in said frame-member and to engage in the apertured hub ofsaid hammer to pivotally mount said hammer in said frame-member; meansto secure one end of said helical spring to the apertured hub of saidhammer; and a resilient reach at the opposite end of said helicalspring, said resilient reach being constructed and arranged to engageand resiliently hold said trigger in a posiand trigger 6 tion to holdsaid sear in cooking engagement with said hammer.

2. A unitary hammer-spring and triggerspring for a firearm embodying aframe-member, a hammer having an apertured hub, a sear, and a triggerhaving an operative connection with said. sear for holding said sear incooking engagementwith said hammer, said unitary hammer-spring andtrigger-spring comprising: a helical spring: constructed and arranged tobe supported in said. frame-member and to engage in the apertured hub ofsaid hammer to pivotally mount said hammer in said frame-member; meansto secure one end of said helical spring to the apertured hub of saidhammer; a resilient reach at the opposite end of said helical spring;and stop-means on said frame-member arranged to engage and hold theresilient reach of said helical spring in engageemnt with said triggerthereby to resiliently hold said trigger in a position to hold said searin cooking engagement with said hammer.

3. A unitary hammer-spring and triggerspring for a firearm embodying aframe-member, a hammer having an apertured hub, a sear, and a triggerhaving an operative connection with said sear for holding said sear incooking engagement with said hammer, said unitary hammer-spring andtrigger-spring comprising: a helical spring constructed and arranged tobe supported in said frame-member and to engage in the apertured hub ofsaid hammer to pivotally mount said hammer in said frame-member; meansto secure one end of said helical spring to the apertured hub of saidhammer; a resilient reach at the opposite end of said helical spring,said resilient reach having a trigger-engaging finger; and stop-means onsaid frame-member arranged to engage the resilient reach of said helicalspring to hold the trigger-engaging finger thereof in enagement withsaid trigger thereby to resiliently hold said trigger in a position tohold said sear in cocking engagement with said hammer.

4. A unitary hammer-spring and triggerspring for a firearm embodying aframe-member, a hammer having an apertured hub, a sear, and a triggerhaving an operative connection with said sear for holding said sear incooking engagement with said hammer, said unitary hammer spring andtrigger-spring comprising: a helical spring constructed and arranged toengage in the apertured hub of said hammer; means to support saidhelical spring in said frame-member; means to secure one end of saidhelical spring to the apertured hub of said hammer; a resilient reach atthe opposite end of said helical spring, said resilient reach having atrigger-engaging finger; and stop-means on said frame-member arranged toengage said resilient reach to hold the trigger-engaging finger thereofin engagement with said trigger to resiliently hold said sear inposition for cocking engagement with said hammer.

5. A unitary hammer-spring and triggerspring for a firearm embodying aframe-member, a hammer having an apertured hub, a sear, a trigger, apivot-pin having a transverse abutment and arranged to pivotally mountsaid trigger in said frame-member, said trigger having an operativeconnection with said sear for holding said sear in cocking engagementwith said hammer said unitary hammer-spring and trigger-springcomprising: a helical spring constructed and arranged to be supported insaid frame-member and to engage in the apertured hub of said hammer topivotally mount said hammer in said frame-member; means to detachablyconnect one end of said helical spring to the apertured hub of saidhammer; a resilient reach at the opposite end of said helical spring,said resilient reach being provided at its free end with atrigger-engaging finger; and stop-means on said frame-member arranged toengage the resilient reach of said helical spring to hold a portion ofsaid reach intermediate its opposite ends in engagement with thetransverse abutment of said pivot-pin to lock said pivot-pin in saidframe-member and to hold the trigger-engaging finger of said reach inengagement with said trigger thereby to resiliently hold said trigger ina position to hold said sear in cocking engagement with said hammer.

6. A unitary hammer-spring and triggerspring for a firearm embodying aframe, a trigger-plate, an assembly-pin provided with a transverseabutment and adapted to secure said trigger-plate in said frame, ahammer having an apertured hub, a sear, and a trigger having anoperative connection with said sear for holding said sear in cockingengagement with said hammer said unitary hammer-spring and triggerspringcomprising: a helical spring arranged to be supported in the saidtrigger-plate and to engage in the apertured hub of said hammer topivotally mount said hammer in said triggerplate; means to detachablyconnect one end of said helical spring to the apertured hub of saidhammer; a resilient reach at the opposite end of said helical spring,said resilient reach being provided with a trigger-engaging finger atits free end; and stop-means on said trigger-plate arranged to engagethe resilient reach of said helical spring to hold the portion of saidreach adjacent said assembly-pin in cooperative engagement with thetransverse abutment thereof to lock said assembly-pin in saidtrigger-plate, and to hold the trigger-engaging finger of said reach inengagement with said trigger so as to resiliently hold said trigger in aposition to hold said sear in cocking engagement with said hammer.

'7. A unitary hammer-spring and triggerspring for a firearm embodying aframe, a trigger-plate having a transverse aperture, an assembly-pinhaving an annular groove and adapted to secure said trigger-plate insaid frame, a hammer having an apertured hub provided with a transversegroove, a sear, a trigger, a pivot-pin having an annular groove andarranged to pivotally mount said trigger in said trigger-plate, saidtrigger having an operative connection with said sear for holding saidhammer in cocked position, said unitary hammer-spring and triggerspringcomprising: a helical spring arranged to be engaged in the transverseaperture of said trigger-plate and in the apertured hub of said hammerto pivotally mount the hammer in said trigger-plate; a finger extendingfrom one end of said helical spring and arranged to engage in thetransverse groove of said apertured hub to secure said spring thereto; aresilient reach extending from the opposite end of said helical spring,said resilient reach being provided with a trigger-engaging finger atits free end; and a shoulder on said trigger-plate arranged to engagethe resilient reach of said helical spring to hold said reach in theannular grooves of said assembly-pin and said pivot-pin respectively tolock said assembly-pin and said pivot-pin in said trigger-plate, and tohold the trigger-engaging finger of said reach in engagement with saidtrigger so as to resiliently hold said trigger in a position to holdsaid sear in cocking engagement with said hammer.

DAVID M. WILLIAMS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 629 I-Ioyt Mar. 10, 1838 290,740Brown Dec. 25, 1883 645,292 Greenough Mar. 13, 1900 2,352,191 GarandJune 27, 1944 2,448,810 Koucky et al Sept. 7, 194B

